Controlling devices for rock drill feeding mechanisms



May 29, 1956 J. A. LARCEN Er Al. 2,747,610

CGNTROLLING DEVICES FOR ROCK DRILL FEEDING MECHANISMS original FiledJuly 19, 1949v INVENToRs. JAN AUGUST LARCEN SVEN LAURENTIUS YTTERFORSUnited States Patent O CGNTRLLING DEVICES FOR ROCKDRILL FEEBINGMECHANISMS an August Larcen, Stockholm, and Sven Laurentius Ytterfers,Steinsberg, Nacka, Sweden, assiguors to Aktiebolaget Atlas Diesel,Nacka,V Sweden, a corporation of Sweden rlgiaai application July 19,1949, Serial No. 105,640, new ateat No. 2,617,388, dated November 11,19572. Divided and this application January 5, 1952, Serial No. 265,132

4 Claims. (Cl. 137-621?) This invention is a division of our co-pendingpatent application Ser. No. 105,640, tiled Iuly 19, 1949, now

U. S. Patent 2,617,388, and relates to controlling devices for rockdrill feeding mechanisms. Such a feeding mechanism may, for instance,consist of an expausible pressure fluid operated feed leg and means onsaid feed leg for supporting a rock drill thereon.

One object of the invention is to provide a controlling device which isadjustable for different feed pressures. Another object of the inventionis to provide a controlling device in which adjustment of a valveprovided in the controlling device may be maintained irrespective of theshocks to which the controlling device is subjected during operation ofthe rock drill. A further object of thev invention is to provide acontrolling device which is cheapV and simple in manufacture and permitsquick and simple operationV and adjustment of a feeding mechanismaccording to prevaihng conditions.

Further objects of the invention Willbe. apparent from the followingdescription and the claims.

in the accompanying drawings one embodiment of a controlling deviceaccording to the invention is illustrated by wav of example. lt shouldbe understood, however, that the invention isY not limited to theembodiment described hereinbelow and may be modified in several diierentways withinthe scope of the claims.

Fig. l is a longitudinalY section through a controlling device accordingto the invention anda portion of a feeding mechanism to whichitisattached. Fig. 2 is a, side elevation and partial section of a: handleforming a part ofthe. controllingdevice according to'Fig. l, and. Fig. 3is a section onlinelillllinfig. 2.

By way of example the controlling device according, to the inventionillustrated in the drawings is provided on a detachable feedingmechanism such asa feed leg comprising a piston rod 8 and a cylinderQhaving a piston (not shown) movable therein and carriedby one end ofthepiston rod S'which at its opposite endvmay support a rock drill.NaturallyV the controlling device accordingrto the invention may also beprovided on the cylinder of a feed leg or another feedingrmechanism asthe case may be and itv should be understood thattheinvention isnotzlimited to the Yuse ofthe controlling device on any particularfeeding mechanism.

The controlling device consists of a housing or block comprising a bodyportion 13 and a sleeve like portion 20 forming a handle. Pressure fluidis supplied to the housing through a hose connection 14 screwed into thebody portion 13 and communicating with a rst passage 15 leading to achamber 15 in the body portion 13. From the chamber 16 a second passage17, 1S leads to an annular groove 12 over an intermediate chamber 19,said groove 12 being formed in the piston rod 8 and communicatingthrough a passage with the interior of the feed cylinder 9. The handleportion 2i) of the housing has internal screw threads 7 and extends fromthe body portion 13 substantially perpendicularly to the piston rod 8.The

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outer end of the handle portion 20 has secured therein a bushing 21 theouter end of which is partially enclosed within a knob 22. The knob 22is secured to a spindle 23 forming a rotatable member for controlling avalve in the housing and carries a screw 24 meshing with the internalscrew'threads 7 in the sleeve 20 with so much play that air may escapealong said threads from the chamber 16 as will be described hereinbelow.A spring 25 is dis.- posed in a bore 26 in the spindle 23, said springserving to push a pressure reduction valve member 27 towards a seat 6formed atV the opening of the first passage 15 in the chamber 16. A stem28 carrying said valve member is slideable in the bore 264 and it iseasily understood that the pressure of the uid in the chamber 16whichcommunicates with the cylinder of the feed leg through the passages17, 13, 10 is reduced with respect to the pressure of the live air inthe passage 15 an` amount corresponding to the amount the screw 24 is`screwed out by means of the knob 22. When the screw 24 is screwed allthe way down by means of the spindle 23 an end face 5 of the spindle23-engages an abutment 4 on the valve member 27 and forces the valvemember towards the seat 6.

The control member for the valve may be arrested in diierent positionsof adjustment by a toothed coupling provided inv the handle portion 20.For this purpose the bushing 21 is provided with radial teeth 29 at theinner end surface of the bushing, saidk teethV cooperating with radialteeth 3i) on a member 31 which is rotatable and axially displaceablewithin thezhandle portion 20. The member 31 consequently forms aAcoupling with the toothed end of theV bushing 21. The member 31 is inconstant engagement with a member 32fthrough two claws 33 on the member32 engaging two corresponding re cesses 34m the member 31. A spring 35is inserted between an abutment 3 in the handle portion 20 and anabutment 2 on. the member 31 andthe spring 35 consequently acts to bringthe teeth 30 into engagement with the teeth 29, so that the knob 22 andspindle 23 are arrested in any position of adjustment. Air leaking fromthe chamber 16- along the threads of the screw 24 may flow through bores36in the spindle 23 through a passage 37 the opening of whichv iscontrolled by the spring loaded ball'valve 3S, furthermore, throughopenings 43 to a space 44 and the atmosphere. A rod 45 is loosely fittedbetween the stem 28Y and the ball valve 33. A, packing 39- prevents airleakage aroundthe-spindle 23, and asv soon as the screw 24 is`screwed-out such. a distancethat the-'valve27 is open the spring load onthe ball. valve-38 forcesv said valve to seated position inwhich theball-valve prevents air leakage from the chamber 16 to the atmosphere,by closing the passage 37;

A spring loaded ball type release valve 41)Y actuated by apush button-41 is'disposed in the intermediate chamber l'and upon actuationY ofsaidpush button 41- opensa third passageV 42. through which air mayescape from the cylim der ofthe feed leg to theat-mosphere irrespectiveof the position-taken bythe knobZZIandsvalve 27., It is obvious that thecontrolling device above described permits very simple control of thefluid flow from the passage 15 to the feeding mechanism, and that thevalve member 27 may be moved from positively closed position asillustrated in the drawings to various open positions in which thetension of the spring 25 is set by means of the knob 22 and defines theamount of pressure reduction in every position. It is also obvious thatpressure release in the feeding mechanism may easily be obtained at anysetting of the valve 27 by pressing the button 41. It is nally obviousthat pressure is released from the feeding mechanism when the screw 24and valve member 27 is screwed all the way down. All these operationsmay be carried out with one hand of an operator holding the handleportion 20.

3 What we claim is: Y 1. A controlling device for rock drill feedingmechanisms comprising a housing separate from the drill, a first passagein said housing for supplying pressure Huid, aV

second passage in the housing for conveying pressure fluid from thehousing to the feeding mechanism, a third passage in the housing forconveying pressure iiuid from the feeding mechanism to the atmosphere,an automatically closing spring actuated release valve in said thirdpassage operable from the exterior of the housing to open the thirdpassage for releasing fluid pressure in the feeding mechanism, a controlvalve in the housing operable from closed position to different openpositions to control the flow of pressure Huid from said tirst passageto said second passage and acted upon in opening direction by the fluidpressure in the first passage, a spring acting on said valve in closingdirection, a member rotatable in the housing for controlling the tensionof said spring, a screw thread in the housing, a screw member forming anabutment for said control valve and engaging said screw thread and foperable by turning of said rotatable member to change the tension ofsaid spring acting on the control valve, a coupling between saidrotatable member and the housing comprising toothed members one of whichbeing locked against rotation in the housing and the other rotatabletogether with said control member, a spring actuating one of saidtoothed members to bring it into engagement with said other toothedmember in various positions of the rotatable member.

2. A controlling device forrock drill feeding mechanisms comprising ahousing separate from the drill, a iirst passage in said housing forsupplying pressure iiuid, a second passage in the housing for conveyingpressure fluid from the housing to the feeding mechanism, a thirdpassage in the housing for conveying pressure uid from the ,feedingmechanism to the atmosphere, an automatically pressure uid from thehousing to the feeding mechanism, a main valve in the housingfoperablefrom closed position to different open positions to control the ilow ofpressure uid from said rst passage to said second passage and acted uponin opening direction by the uid pressure in the first passage, a springacting on said main valve in closing direction against said uidpressure, a rotatable handle on the housing accessible from the exteriorof the housing during operation for controlling the tension of saidspring, and coupling means between said handle and the housingcomprising a non-rotatable coupling portion Y in the housing and acoupling portion rotatable with said handle, spring means for urgingsaid coupling portions into engagement, said coupling portions beingmutually movable against spring pressure in the handle to permitengagement and disengagement of said non-rotatable and said rotatablecoupling portion and thereby arresting or releasing the handle indifferent positions f adjustment for setting the tension of the mainvalve actuating spring.

4. A valve block for rock drill feeding mechanisms comprising a housingseparate from the drill, a first passage in said housing for supplyingpressure fluid to the housing, a second passage in the housing forconveying pressure liuid from the housing to the feeding mechanism, amain valve in the housing operable from closed position to differentopen positions to control the flow of pressure tiuid from said irstpassage to said second passage and the pressure of the iiuid in thesecond passage, a rotatable closing release valve in said third passageoperable from the exterior of the housing to open said third passage topermit escape of pressure fluid from the feeding mechanism to thevatmosphere upon actuation of lsaid release valve, a main valve in thehousing operable from closed position to different open positions tocontrol the flow of pressure iiuid from said iirst passage to saidsecond passage and acted upon by the pressure fiuid,'a spring acting onsaid main valve against the pressure fluid, a rotatable handle on thehousing accessible from the exterior ofthe housing during operation forcontrolling the tension of said spring, and coupling means between saidhandle and the housing comprising a non-rotatable member in the housingand a member rotatable with said handle, spring means for urging saidmembers into engagement, said members being mutually movable againstspring pressure axially of the elongated handle in engaging anddisengaging said non-rotatable member and thereby Aarresting orreleasing the handle in different positions of adjustment for settingthe tension of the main valve actuating spring. 3. A controlling devicefor rock drill feeding mechanisrns comprising Va housing separate fromthe drill, a rst passage in said housing for supplying pressure fluid tothe housing, a second passage in the housing for conveying handle on thehousing accessible from the exterior of the housing during operation forsetting said main valve in various positions of adjustment, means forVsecuring said valve block on the feeding mechanism, and coupling meansbetween said handle and the housing comprising a non-rotatable couplingportion in the housing and a cou-V pling portion rotatable with saidhandle, one of said coupling portions being provided with groove meanseX- tending radially of said handle and the other coupling portion withmatching cam means, said coupling portions being mutually movable topermit engagement and disengagement of said cam and groove means andthereby arresting or releasing the handle in different positions ofadjustment for setting said main valve.

References Cited in the tile of this patent UNITED STATES PATENTS 84,586Shackleton Dec. l, 1868 394,424 Wilkinson Dec. 11, 1888 905,745 Orr Dec.1, 1908 1,044,106 Vidar Nov. 12, 1912 1,095,105 Goodwin Apr. 28, 19141,108,245 Schebler Aug. 25, 1914 1,138,338 Whitney' May 4, 19151,287,126 Smith Dec. 10, 1918 1,641,892 Lane Q Sept. 6, 1927 2,039,638 lDruge May 5, 1936 2,075,341 Goodman Mar. 30, 1937 FOREIGN PATENTS 1,006Great Britain 1882

